If a software error corrupts a data object, or if erroneous data updates the data object, a data protection administrator may restore the data object to a previous state that does not include the corrupted or erroneous data. A backup/restore application executes a backup operation either occasionally or continuously to enable this restoration, storing a copy of each desired data object state (such as the values of data and these values' embedding in a database's data structures) within dedicated backup files. When the data protection administrator decides to return the data object to a previous state, the data protection administrator specifies the desired previous state by identifying a desired point in time when the data object was in this state, and instructs the backup/restore application to execute a restore operation to restore a copy of the corresponding backup files for that state to the data object.
A virtual machine is a software implementation of a computer that executes programs like a physical machine. A system virtual machine provides a complete system platform which supports the execution of a complete operating system, and usually emulates an existing architecture, including disks. Multiple instances of virtual machines lead to more efficient use of computing resources, both in terms of energy consumption and cost effectiveness, known as hardware virtualization, the key to a cloud computing environment. Similar to other data objects, backup copies may be made of virtual machine data objects to enable a restoration of the virtual machine data objects in the event of corruption or an erroneous update to the virtual machine data objects.
An image is a capture of a state of a data object, such as a file system, a virtual machine, or an application, at a specific moment in time. A data object may be stored on a storage array, which is a disk storage system that includes multiple disk drives. Unlike a disk enclosure, a storage array has cache memory and advanced functionality, such as virtualization and Redundant Array of Independent Disks (RAID). A data protection administrator may manage a backup/restore application to create images of data objects and store the images of data objects on multiple storage arrays.